1. Technical Field
This application relates to UMTS (Universal Mobile Telecommunications System) in general, and to an apparatus and method of uplink data during cell update in universal mobile telecommunications system user equipment in particular.
2. Description of the Related Art
UMTS is a third generation public land mobile telecommunication system. Various standardization bodies are known to publish and set standards for UMTS, each in their respective areas of competence. For instance, the 3GPP (Third Generation Partnership Project) has been known to publish and set standards for GSM (Global System for Mobile Communications) based UMTS, whereas and the 3GPP2 (Third Generation Partnership Project 2) has been known to publish and set standards for CDMA (Code Division Multiple Access) based UMTS. Within the scope of a particular standardization body, specific partners publish and set standards in their respective areas.
Consider a wireless mobile device (UE) that complies with the ETSI specifications for the UMTS protocol. If the need arises to transmit data from the UE towards the UTRAN, while a Cell Update is in progress (i.e. a CELL UPDATE message has already been sent to the UTRAN), the data may be lost because the required channels may not be useable. (Cell Update is described in section 8.3.1 of the 3GPP standard 25-331).
Standard document ETSI TS 125 331 v3.10.0 (2002-03) addresses the subject of UMTS RRC (Radio Resource Control) protocol requirements between UTRAN (Universal Terrestrial Radio Access Network) and UE (User Equipment). Although ETSI TS 125 331 describes how the UE should behave during a Cell Update with the UTRAN, the document may not enable the UE for uplink data during a Cell Update in particular.